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*Moderator's note: Spin off from previous thread due to advanced nature of topic.*

There is classical field theory too, and GR is a relativistic classical field theory of the gravitational interaction. It's ironic that you fight for a geometrical-interpretation-only point of view and at the same time forbid the discussion of a very strong argument for this point of view: Starting from the gauge-theoretical approach (making Poincare transformations local) you end up inevitably with the geometrical point of view. If you restrict yourself to the classical description of spin-saturated matter and electromagnetism you even end up with GR proper, i.e., a pseudo-Riemannian (Lorentzian) manifold. Including spin you are lead to Einstein Cartan theory, i.e., a spacetime manifold with torsion, which is however still a theory where the gravitational interaction is geometrized as in GR, it's only a bit more comprehensive.If we consider GR as an "effective field theory", i.e., as a low energy approximation to some underlying quantum theory,thenyes, we can consider gravity as an "interaction" on that view. That is the view that Weinberg, for example, is advocating in the article you linked to. But that view is off topic in this forum; discussion of it belongs either in the quantum physics forum, or more likely in the Beyond the Standard Model forum since that's where discussion of quantum gravity in general belongs. See my post #3 for further discussion of this point.

All this has nothing to do with quantum field theory. The question, whether a future consistent quantum theory of gravitation will be a QFT or based on some more general concept, is of course wide open, and discussions/speculations about this indeed belongs in another subforum.